I've worn glasses for most of my life and can count on one hand the number of frames I've had in that time. But when my beloved frames had been repaired for the third time and couldn't be repaired anymore, I had to go through the arduous task of choosing a new pair. Here are some things I've learned:

It doesn't matter how much you love a pair of frames, if they don't suit you, they don't suit you. I love big, round, thick frames. But I don't love looking like a bug-eyed insect.

Try each pair on for more than 5 seconds. Do they look good? And more importantly, do they feel good? There is nothing worse than having to wear a pair of frames that hurt.

Although my instinct was to go for black so they'll be more versatile, I tried on lots of different colours too. You never know what is going to light up your face and bring out your eyes.

Find a size/shape that suits you face and then find variations on the theme. I found that narrower, rectangular shapes suited me best.

Take a friend to help you decide. But only one who is going to tell you the honest truth. If all else fails, ask everyone in the shop. Strangers may be less likely to care about your feelings and tell you the truth.

This process can take a while and I've definitely learnt what suits
me and what doesn't. I've returned two pairs (luckily I have a very
understanding optometrist) and have had to go back to have some
readjusted more than a few times. But I now have not only one, but four
pairs of frames that I love and can choose from daily. It is totally
worth the perseverance!